Post-traumatic stress and criminal behaviour: Re-offending risk and personal constructs Traumatic life events may lead to diverse psychopathological outcomes alongside different symptom constellations. This study aimed to investigate the relationship between early victimization, PTSD symptoms and re-offending risk in prisoner populations. The overall hypothesis was that dysfunctional cognitions (i.e. worry, negative perception of others’ support) may mediate between PTSD and re-offending risk. Further, this study explored the personal construct explanatory model of PTSD based on Kelly’s theory (1995) that a person who experiences a traumatic event which cannot be construed in relation with other life events, may created a fragmented trauma-related construct subsystem. Results partially confirmed the hypothesis showing a role of negative perception of other’s support in the mediation between PTSD and re-offending risk. Participants with PTSD symptoms were less able to integrate their traumatic experience and their offence into their construct system.Keywords: Trauma, PTSD, cognitive construct, re-offending risk.